Gunn has been sharing photos from the film’s set every day on social media. Last week, Gunn shared a photo of himself with actor Spencer Wilding who played the guard that stole Star-Lord’s cassette player. Wilding is seen with a small package of Play-Doh given to him by the director.

“I would keep a pile of little Play-Doh containers onset and if someone did an especially amazing job that day – whether it was an actor, a grip, a stunt man, or a PA (production assistant) – they’d get a canister of Play-Doh,” Gunn wrote in a lengthy post. “I probably only gave about 40 containers out over the entire shoot – on an 85 day schedule with a crew of a couple hundred, that isn’t much.”

Gunn said he decided to choose Play-Doh because he loves its smell.

“Opening a new container and smelling it puts me in a creative, child-like place. And who doesn’t love playing with Play-Doh,” wrote Gunn.

He added that Spencer received the reward for acting out a scene that got cut from the final film in which he danced through the prison with the Sony Walkman.

The scene will be on the Blu-Ray for the film when it comes out, according to Gunn.

That could be a while since the film is still going strong at theatres. “Guardians of the Galaxy” has become the first film this year to cross $US300 million at the domestic box office.